The main security concerns on all Windows versions are those of users being duped into installing rogue software such as fake patches, browser plugins or antivirus programs, and of browser plugins such as Flash or Acrobat which have security holes.

To mitigate the former, bar ordinary users from installing software by making them limited users, or by way of a software restriction policy.

http://sourceforge.net/projects/softwarepolicy/ may be of help here.

As for browser plugins, remove those which are not actually needed to minimise the attack surface. In reality, only the Flash Player plugin is needed on most computers, the rest can be disabled or removed (including Acrobat/Adobe, surprisingly) If Sun/Oracle Java is installed, remove that too since it is often used as a secondary attack vector for browser plugin vulns. And no, virtually no webpages use Java these days. Java and Javascript are entirely different.

If remaining on XP you should strongly discourage the use of Internet Explorer, as that will no longer be patched. Install Firefox or an alternative, which is supported by its vendor.

If so many important systems still running XP, (ATMs, healthcare, electric/gas utilities, etc) will be at risk after April, can Microsoft offer an almost free upgrade to Windows 7 Home Premium, and show that they care what happens after the end of the support?

Another point. "Silver told us many late-comers are removing admin rights, restricting permissions, and otherwise locking down any XP systems that can't be retired."Shouldn't business, corporations, industries, etc have done that a long time ago, regardless of the end of the XP's support? No wonder why so many systems get hacked.

No doubt. Last I'd heard, Apple actually has more market share than anyone else in the $1000+ PC market. But virtually all Apple computers (certainly the ones that sell in greatest volume) fall in that category. Nice machines, but expensive. Given that so many companies say they're sticking with XP due to upgrade costs, I don't imagine many of them are going to jump to Apple.

I gave been asked that a few times this week. People think they have to upgrade, that what they are using isn't safe. If your definition of not being safe is running an OS that isn't being patched then yes. When I think of not being safe I think of sitting in the middle of a busy road or txting while driving... things that will harm you physically.

If you just use your computer for email and web browsing with some office apps mixed in and run anti virus I think you can rest comfortably. You don't need to run out and upgrade to 7.

If you are a business and those XP machines will not touch the internet then your ok. If they do then you better at least have a plan to upgrade. Those machines will be security holes in your network.

You know, it's interesting; not all XP users are going to upgrade over the next few months, but tens of millions of them will-- and all of that market share has to go somewhere. It could mean Windows 7 gets a boost, but it could shake down some other ways too.

That said, no one I interviewed for this story felt that a major shake-up is in the cards. Mike Silver said consumers are certainly turning away from Windows but that corporate environments are unlikely to experience a major OS shift. Dave Johnson said Mac OS X is gaining market share in the enterprise at around 1% annually, and that both Macs and Chromebooks could receive more enterprise attention after XP goes dark-- but he also didn't feel businesses are about to drop Windows en masse. Apps and services are moving from the OS to the browser and cloud, and both analysts mentioned that trend as significant to the future of Windows, however. Personally, I have no doubt that Windows 7, OS X, Chrome and Linux will all gain share, and I suspect Windows will fall below 90% PC market share-- but beyond that, it's tough to say how quickly bigger changes might unfold.

What do readers think? A lot of those XP licenses are going to get replaced by something. What OS do you see gaining? Are some of you moving to Windows 7 or 8? Jumping to Mac? Shifting to tablets for most things? Sticking with XP?

This going to be the calamity what Y2K never was. Why? Because every one was prepared for Y2K, and responsible people who should know better are burying their heads in the sand this time around. I wonder where the responsibility is going to lie for the catastrophes that will be sure to occur. I plan on having an extra supply of cash, my prescriptions, and ready-to-eat food that doesn't need to be cooked by April 8.

I winder, would it be legal for another organization to take control of this abandoned operating system, still adequate for those of us who aren't software developers, and supply updates and such?

Nope, you're not missing anything; it was just phrased ambiguously. I wasn't trying to convey degree of difficulty but rather degree of XP removal--i.e. keeping it around in virtual environments represents a lesser degree of removal than moving wholesale to Windows 7.

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